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#include "comparison_helper.h"

float randf()
{
	return (float)rand() / (float)RAND_MAX;
}

SquareMatrixState createRandomCovarianceMatrix()
{
	// Create a symmetric square matrix
	SquareMatrixState P;

	for (int col = 0; col < State::size; col++) {
		for (int row = 0; row <= col; row++) {
			if (row == col) {
				P(row, col) = randf();

			} else {
				P(col, row) = P(row, col) = 2.0f * (randf() - 0.5f);
			}
		}
	}

	// Make it positive definite
	P = P.transpose() * P;

	return P;
}
